Design of a Hybrid Dryer for Hemp Flowers for the Inter-Andean region of Ecuador

Abstract
The hemp flower has gained relevance in the agroindustrial and medical field worldwide due to the analgesic, antiinflammatory, and antiepileptic benefits that cannabidiol offers. A critical process in post-harvest is drying, as this allows to maintain the intrinsic properties of the flower. This operation requires a constant heat supply that involves high energy consumption. Therefore, a dryer was designed that uses a hybrid heat supply system based on solar thermal and electric energy. For this, a design of the chamber with a dome cover capable of taking advantage of solar radiation was made together with a system of collectors, supported by an electrical resist for periods of low irradiance. A theoretical analysis of the process was carried out considering the speed and temperature as study parameters and was validated by simulation and dynamic fluid modeling (CFD), obtaining that the thermal power to dry 120kg of the flower is 8.52kW, supplied by 4 solar collectors in series, the dome-type cover, and a tubular resistance of 2kW. The proposed design meets the requirements for maintaining a temperature of 50 ° C within the chamber during the drying time and a speed of 0.5m/s, which guarantees that the product is dehydrated without affecting its organoleptic properties and quality. Furthermore, the project will contribute as a benchmark for technological innovation in the use of renewable energy sources in Ecuador.